NAND flash memory, as well as other types of non-volatile memories (“NVMs”), are commonly used for mass storage. For example, consumer electronics such as portable media players often include flash memory to store music, videos, and other media.
NVMs, however, may develop defective memory cells through everyday use, and operational memory cells may suffer from program/erase/read disturb due to voltages applied to neighboring cells. A block of a NVM that have one or more of these non-operational memory cells may be referred to as a “bad block”.
Conventionally, when a system determines that a block of a NVM is a bad block, the system may retire the entire block. Unfortunately, such a scheme reduces the pool of remaining programmable blocks in the NVM and also leads to increased cycling of the remaining blocks. Both of these factors can shorten the lifespan of the NVM.